Hidden/Secret properties in toString

[XanderD99]

Is your feature request related to a problem? Please describe.
I want to hide certain fields from the toString function or at least make them secret.

Describe the solution you'd like
Perhaps a new tag you can add to properties to ignore them from the toString function or maybe a @secret tag that swaps the real value with ***** for example.

Describe alternatives you've considered
none :)